Question

Wolfram Alpha Help- limits

Answer 1

How is it that the asnwer to these two are different i thought the negative made the fraction the same no matter what side u put it on

Answer 2

http://www.wolframalpha.com/input/?i=lim+(-x%5E2-4)%2F(x%2B2)+as+x-%3E-2

Answer 3

http://www.wolframalpha.com/input/?i=lim+-((x%5E2-4)%2F(x%2B2))+as+x-%3E-2

Answer 4

it looks like you want to know why -(x^2+4) isn't the same as -x^2-4 ?

Answer 5

they are thoug h

Answer 6

by the distributive property

Answer 7

oh one you have on that one link is -(x^2-4) not -(x^2+4)

Answer 8

so you are comparing -(x^2-4) to -x^2-4
yep this aren't the same

Answer 9

-(x^2-4)=-x^2+4
notice this isn't the same as -x^2-4

Answer 10

Ohh!! Thank you. Wait so if i changed the top 4 do i also have to change the bottom? or do i only have to change one side?

Answer 11

i'm not totally sure what you mean

Answer 12

Like since its in front of the fraction does it multiply Negative by the whole fraction or only one side?

Answer 13

\[-\frac{a}{b}=\frac{-a}{b} \text{ or } \frac{a}{-b} \]

Answer 14

but this definitely does not equal -a/-b

Answer 15

which would be a/b

Answer 16

No i mean like since it was like this \[-((x^2+4)/(x+2))\]

Answer 17

\[-(\frac{a}{b})=-\frac{a}{b}\]

Answer 18

The negative is outside the whole parenthesis so do both of the bottom and top fraction change symbols?

Answer 19

it is like saying -1 * a/b

Answer 20

no -1 is not equal to -1/-1

Answer 21

Oh ok thanks so all i ahd to do was change that 4 to a plus?

Answer 22

Thanks

Answer 23

\[-x^2-4 \text{ is the same as } -(x^2+4)\]

Answer 24

I guess that is what you are asking

Answer 25

Yeah but!

Answer 26

-((x-1)/(x-1)) shouldnt it makes both 1's postivie a both X's negative

Answer 27

no again -1 is not equal to -1/-1

Answer 28

oh wait that's the same thing

Answer 29

Yeah i got it thank you

Answer 30

Have a good night

Answer 31

\[-1(\frac{x-1}{x-1})=\frac{-1(x-1)}{x-1} \text{ or } \frac{x-1}{-1(x-1)}\]